Process of extracting oil, grease, and the like from oil-bearing material.



No. 807,567. 'PATENTED DEO.19,1905. E. J. MAYWALD. PEooEss 0P EXTRACTINGOIL, GREASE, AND THE LIKE FROM OIL BEARING MATERIAL.

APPLIUATION FILED OOT.6, 1902. RENEWED APR. 26,1905.

UNITED STATES PATENT oFrIoE.

FREDERICK J. MAYWALD, OF NEW YORK, N. Y., ASSIGNOR TO EDWARD H.FALLOVVS, OF NEW YORK, N. Y.

PROCESS OF EXTRACTING OIL, GREASE, AND THE LIKE FROM OIL-BEARINGMATERIAL.

Specification of Letters Patent.

Patented Dec. 19, 1905.

Application filed October 6, 1902. Renewed April 26, 1905. Serial No.257,428.

To aZZ whom it may concern:

Be it known that I, FREDERICK J. MAY- WALD, a citizen of the UnitedStates, residing in the city of New York, borough of Brooklyn, and Stateof New York, have invented certain new and useful Improvements inProcesses for Extracting Oil, Grease, and the Like from Oil-BearingMaterial; and I do hereby declare the following to be a full, clear, andexact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

My invention relates to improvements in separating and extracting oil,grease, and the like from materials floating in or held in suspension inwater or other liquid; and my invention is particularly applicable tothe extraction of oil and grease from animal and vegetable matter-such,for instance, as slaughter-house material, fish and fish-waste, garbage,and the like after the same have been subjected to digestion to liberatethe oil and grease from the fibrous and cellular structures in which thesame are contained and from tankage. It is also applicable to theextraction of oil from boiler-feed water.

My invention consists, essentially, in adding carbon tetrachlorid (C014)to liquid containing oil or grease or to a mass of oil or grease bearingmaterial floating in or in suspension in Water or other liquid of lessspecific gravity than the carbon tetrachlorid and permitting the carbontetrachlorid to descend through the mass of material treated, which itwill do by reason of its greater specific gravity, and to collect in thelower portion of the vessel in which the treatment is conducted. In sopassing down through the mass treated the carbon tetrachlorid willdissolve the oil and grease present in the mass, carrying the same downwith it. The carbon tetrachlorid may be drawn off as or after itcollects, as just described, and the oil and grease extracted bydistillation.

This process is rendered possible by the fact that carbon tetrachloridhas relatively great specific gravitynamely, about 1.6so that itseparates readily from water and lighter liquids by difference inspecific gravity alone, even when it carries a large amount of oil andgrease in solution. It is therefore much easier to separate carbontetrachlorid from a mass of material such as above described than it isto separate naphtha (the solvent heretofore usually employed for thepurpose) from such a mass, and in addition carbon tetrachlorid has thefurther great advantage that it is non-inflammable either as a liquid oras a vapor, whereas the inflammability of naphtha constitutes a seriousand in many cases a prohibitive objection to its use in the extractionof oil and grease. Furthermore, carbon tetrachlorid is not injurious totlclle human system and has no disagreeable 0 or.

The object of my invention is to extract oil, grease, and the like fromoil-bearing material in a simple,rapid, and economical man ner withoutdanger of fire and without discomfort or danger to persons in proximityto the apparatus.

In carryingout my invention the treatment is preferably conducted in aclosed vessel provided with means for digesting its contents and withsuitable taps or the like for drawing ofi the carbon tetrachlorid withthe oil and grease in solutiontherein from the bottom of the vessel. Thematerial to be treated having been placed in such a vessel and thecarbon tetrachlorid having been added in suitable quantities thecontents of the vessel are preferably agitated, thus bringing the carbontetrachlorid into intimate contact with the oil and grease bearingmaterial. The contents of the vessel are then allowed to settle,whereupon the carbon tetrachlorid, with oil and grease in solutiontherein, will quickly separate from the water and solid residue becauseof its relatively great specific gravity and its comparatively slightviscosity, falling to the bottom of the vessel, while the-water andsolid residue rises above the same. The carbon tetrachlorid may then bedrawn off from the vessel and separated from the oil, grease, and thelike which it carries in solution in any suitable manner as, forexample, by distillation and condensation. Because of its lowboiling-point it is easy to separate carbon tetrachlorid from thematerials which it carries in solution and from any water which may becarried over with it by distillation.

In the accompanying drawing I illustrate diagrammatically an apparatuswhich may be used for the above treatment. Such an apparatus consists ofa closed vessel 1, having a charging-opening 2 at its top and adischarge outlet or passage 3 at its bottom. A

I pipe 4 for drawing ofi the tetrachlorid may be connected to thisoutlet-passage, and in this pipe there may be a glass sight-tube 5. Thevessel may be provided with a mechanical agitator 6. Such a vessel mayalso be used for carrying on the preliminary-digestion process such asis now commonly used in the extraction of oil and grease. after thedigestion is complete and after so much of the oil and grease as can beremoved without the use of a solvent has been removed carbontetrachlorid is admitted to the vessel through a pipe 7 or in any othersuitable way and is mixed with the fluid and solid contents of thevessel by means of the agitator. The contents of the vessel are thenallowed to separate, whereupon the carbon tetrachlorid will quicklycollect in the lower portion of the vessel and in the discharge-passage3, which at that time is closed by means of its valve 8. The carbontetrachlorid may be drawn off through the pipe 5, the progress of theoperation being watched through the window 4, and the appearance of anysolid matter at this Window indicates that the carbon tetrachlorid hasbeen drawn off, since the solid matter present will float 011 thesurface of the carbon tetrachlorid. In this way substantially all of thecarbon tetrachlorid may be drawn off, there being little or no waste.

Apparatus for separating the carbon tetrachlorid from the oil and greasein solution therein by distillation is not shown or de- In such casescribed, since distilling apparatus for similar purposes is well known.

The use of the closed vessel for carrying out the above process preventsannoyance from the oifensive fumes which the material treated oftengives off.

What I claim is 1. The herein-described process of sepa-' rating andextracting oil, grease, and the like from water or similar liquid andfrom material floating in, or in suspension in, Water or similar liquid,which consists in adding carbon tetrachlorid to the mass and permittingthe same to descend therethrough and separate therefrom by difference inspecific gravity.

2. The herein-described process of separating and extracting oil,grease, and the like from water or similar liquid and from materialfloating in, or in suspension in, water or similar liquid, whichconsists in adding carbon tetrachlorid to the mass and permitting thesame to descend therethrough and separate therefrom by difference inspecific gravity, drawing off the carbon tetrachlorid, and thenseparating the same from the oil, grease and the like in solutiontherein by distillation. I

In testimony whereof I afiix my signature in the presence of twoWitnesses.

FREDERICK J. MAYVVALD.

Witnesses:

HARRY M. h lARBLE, D. HOWARD HAYROOD.

